1. Field of the Invention
The present invention relates broadly to spacers used in laying tile. In particular, the present invention relates to spacers made of a foamed polymeric material and a method of using the spacers made of foamed polymeric material in laying tile on floors, walls and like places.
2. State of the Art
In laying tile, the usual procedure is to apply a coating of mastic or cement to the substrate or surface that is to be tiled. The individual tile pieces are then placed edge to edge on the substrate in contact with the mastic or cement. For appearance as well as good construction, the tiles are laid with relatively narrow joint spaces between mutually adjacent edges thereof. After the mastic or cement has cured and the tiles are firmly adhered to the substrate, the narrow joint spaces between the tiles are filled with a grout.
Laying of tiles with joint spaces between the tiles has its disadvantages due to the difficulties experienced by the mason in maintaining uniformity of the joint spaces as the tiles are being laid. Uniform joint spacing is necessary to maintain desirable alignment of the rows and columns of tiles. It has been customary to place a spacer element between the tiles as they are being laid, with the spacer element being removed after the tiles have been firmly secured to the substrate by curing of the mastic or cement. Following removal of the spacers, the open joint spaces are then filled with a grout.
Early practice was to place a heavy cord or string between the tiles as they were being laid. After the mastic or cement had cured and the tiles were firmly adhered to the substrate, the cord or string was removed and the spaces between the tiles were filled with grout. In U.S. Pat. Nos. 2,031,684 and 2,930,135 there are disclosed small spacer elements made of rubber or other plastics materials which are designed to be placed between the tiles at mutually respective corners of adjacent tiles. In the first mentioned patent, the spacers have a thickness which is substantially less than the thickness of the tiles, such that the spacers need not be removed. Instead, the grout was simply filled into the spaces between the tiles and over the spacers. Problems were inherent in such a system. The grout placed over the spacers had a tendency to break loose and fall from the tiled structure. Additionally, because of the thinness of the spacers, they were hard to use and it was still difficult to maintain uniform spacing between tiles.
The spacers of U.S. Pat. No. 2,930,135 were thicker than those of U.S. Pat. No. 2,031,135 and were designed to be removed from between the tiles after the mastic or cement had firmly adhered the tiles to the substrate. However, these spacers had their drawbacks also. It was a tedious, time consuming job for the mason to take a probe, such as an awl or screwdriver, and remove the spacers from their positions between the tiles. The spacers often became firmly adhered to the mastic and were hard to remove.
In an earlier, somewhat less relevant patent (U.S. Pat. No. 1,836,964), it had been proposed to first adhere an underlying foundation sheet to the substrate. The foundation sheet had raised portions which provided guides for laying the tiles. A major problem with such a system is the adherence of tile to the foundation sheet as well as the tendency for the grout to fall from the spaces between the tile due to poor adhesion to the foundation sheet.